Driving mechanisms for loom jacquards



Dec. 5, 1967 Filed Oct. '7, 1965 R. NEYRAUD DRIVING MECHANISMS FOR LOOM JACQUARDS 3 Sheets-Sheet 1 Dec. 5, 1967 NEYRAUD 3,356,109

DRIVING MECHANISMS FOR LOOM JACQUARDS Filed Oct. 7, 1965 5 Sheets-Sheet 2 INVENTOR I Qua War/ g ATTORNE$ Dec. 5, 1967 R. NEYRAUD 3,356,109

DRIVING MECHANISMS FOR LOOM JACQUARDS Filed Oct. 7, 1965 5 Sheets-Sheet 5 4am I W r/1m BY )QMQ ATTORNEK United States Patent 3,356,109 DRIVING MECHANISMS FOR LOOM JACQUARDS Ren Neyraud, Lyon, France, assignor to Societe des Mecaniques VERDOL, Lyon, Rhone, France, a French limited-liability company Filed Oct. 7, 1965, Ser. No. 493,666 Claims priority, application France, Dec. 18, 1964, 45,412/ 64 3 Claims. (Cl. 139-1) ABSTRACT OF THE DISCLOSURE The mechanism comprises an inlet shaft connected with the loom, an outlet shaft connected with the Jacquard, a first clutch interposed between these shafts to connect same with each other at a single relative angular position, an auxiliary driving motor to permit of rotating the outlet shaft and the Jacquard at a slow speed independently of the loom, a second clutch between the auxiliary motor and the outlet shaft and an irreversible speed reducing gearing between the second clutch and the auxiliary motor'in order that the Jacquard may never rotate the outlet shaft and the motor when the first clutch is ineffective and the second clutch effective.

This invention relates to Jacquards for looms.

In the conventional arrangement the Jacquard is generally connected with the loom by means of a chain gearing. When the operator notices a defect on the patterned fabric, he stops the normal operation of the loom and operates it backwards at reduced speed in order to .unweave the fabric until the defective weft is eliminated.

During this backward rotation of the loom the Jacquard itself runs backwards to form again in the inverse order the successive sheds which permit of extracting the successive wefts, modern J acquards comprising means whereby such backward operation is possible. The disadvantage of this unweaving operation is that at each pick of the loom the beating-up reed rubes against the warp threads as during normal operation. Consequently in the portion of the fabric which follows the defective weft the warp threads are submitted to three successive rubbing steps, namely during the initial operation of the loom, during backward rotation thereof and when normal weaving is resumed starting from the defective weft. This repeated rubbing often noticeably deteriorates the threads. Further the Wefts which are immediately in front of the defective one are more or less affected three times by the beating-up action of the reed. As a result of the above actions, undesirable moir effects may appear on the fabric in the zone which corresponds to the initial defective weft; I

The present invention has for its object to avoid the above disadvantages by operating the Jacquard backwards at reduced speed independently of the loom which is left at standstill, in order that the successive sheds may be formed and that the successive weftsmay be removed from'th'e fabric whilethe reed remains stationary at its conventional rearmost position.

Another object of this invention isto provide a Jacquard driving mechanism comprising an inlet shaft permanently "connected with the loom, an outlet shaft 5 by the branches 17 of a bifurcated Free permanently connected with the Jacquard, and means to connect the outlet shaft either with the inlet shaft during normal weaving operation of the loom, or with a slow-speed driving apparatus which permits of operating the Jacquard either backwards or forwards at a reduced speed independently of the loom during the unweaving operation.

A further object of the present invention is to so arrange the connecting means provided between the inlet shaft and the outlet shaft of the driving mechanism that when normal operation of the loom is resumed after the Jacquard has been run backwards, the proper angular relation between the said inlet and outlet shafts is automatically restored.

Still another object of the present invention is to provide a driving mechanism of the character described, wherein the slow-speed driving apparatus is irreversible in order to be unaffected by the tendency of the shaft of the Jacquard to rotate in one or the other direction under the action of the lingos, of the tension of the warp threads, etc. In a preferred embodiment the slowspeed driving apparatus is in the form of an electric motor associated with a worm-and-wheel speed reducing gearing.

In the annexed drawings:

FIG. 1 diagrammatically shows the general disposition of a loom provided with a driving mechanism according to the present invention.

FIG. 2 is a view in elevation of the rear side of the mechanism.

FIG. 3 is a plan view thereof.

FIG. 4 is an end view thereof.

FIG. 5 is an axial section of the one-tooth clutch of the mechanism.

With reference to FIG. 1, the driving mechanism A according to the invention is normally adapted to connect a Jacquard B with the corresponding loom C while permitting of rendering the Jacquard independent of the loom during the unweaving operation. This mechanism may conveniently be mounted above the loom, relatively close to the Jacquard, as shown.

The driving mechanism A comprises an inlet shaft 1 and an outlet shaft 2 rotatably carried by two lateral frame members 3 and 4. The inlet shaft 1 is permanently connected with the loom C by means of a chain 5, while the outlet shaft 2 is permanently connected with the Jacquard B by another chain 6.

The inlet shaft 1 carries the hub 8a (FIG. 5) of a circular plate 8, the said hub being fixed angularly and axially on the shaft as for instance by means of transverse pins 7. A longitudinal key 9 is secured onto hub 8a and a sleeve 10 is slidably mounted on the hub and on the key in order to rotate with shaft 1 while being axially free thereon. Springs 11 are interposed between the circular plate 8 and an end flange 12 formed on the slidable sleeve 10 to urge the latter towards the right in FIG. 5, as indicated by the arrows 13.

The end of the slidable sleeve 10 opposed to flange 12 is formed with a laterally protruding tooth 14 which extends through an angle of with respect to the axis of the shaft 1 (see FIGS. 3 and 5). The central portion of the sleeve has a circular groove 15 in which are engaged two diametrically opposed pins 16 carried lever mounted on a transverse shaft 18, When this lever 17 rocks counterclockwise in FIG. 5, it displaces the slidable sleeve towards the left against the action of springs 11. In the example illustrated actuation of lever 17 is insured by an electromagnet 19 with which it is connected by means of a link 20 (FIG. 4) and of an arm 20a keyed on shaft 18.

The inlet shaft 1 further loosely supports a sleeve 21 (FIGS. 3 and 5) one end of which has a sprocket wheel 22 which is connected by a chain 23 with another sprocket wheel 28 keyed on the outlet shaft 2. The proper tension of this chain 23 is insured by a tensioning roller 29 of conventional type, rotatably carried by an eccentric supported by a fixed trunnion 30. The other end of sleeve 21 is formed with a single lateral tooth 24 which extends through an angle of 180 to cooperate with the single tooth 14 of the slidable sleeve 10. The loose sleeve 21 is retained axially on shaft 1 by appropriate means not shown, as for instance by the adjacent lateral frame member 3 and by the adjacent end of the hub 8a of the circular plate 8.

The mechanism further comprises a microswitch 26 (FIG. 5) the actuating arm of which carries a roller 25 adapted to be pushed by the flange 12 of the slidable sleeve 10 when the latter is displaced towards the left in FIG. 5 against the action of springs 11.

This microswitch 26 controls an electromagnetic clutch 27 mounted on the outlet shaft 2, close to the lateral frame member 4, in order to connect with the said shaft a gearwheel 31 of relatively large diameter loosely carried by the said shaft. The electromagnetic clutch 27 may be of any conventional type and therefore its inner construction need not be illustrated and described. It may be connected with its controlling circuit by any known means, as for instance by slip rings and brushes.

The frame members 3 and 4 further support an electric motor 32 which drives an irreversible speed-reducing gearing 33, as for instance of the worm-and-wheel type, and the outlet shaft of this gearing carries a pinion 34 which meshes with the above-described gear wheel 31.

The driving mechanism operates as follows:

At the normal operating position illustrated in the annexed drawings, the teeth 14 and 24 of the respective sleeves 10 and 21 are in mutual engagement and therefore the inlet shaft 1 and the outlet shaft 2 are connected with each other by the aforesaid sleeves, sprocket wheel 22, chain 23 and sprocket wheel 28, so as to rotate in unison. In the example illustrated the diameter of sprocket wheel 28 is twice the diameter of sprocket wheel 23 and therefore shaft 2 rotates at half the speed of shaft 1. Flange 12 being at its right-hand position in FIG. 5, roller 25 is free and microswitch 26 is open. Clutch 27 is unenergized and therefore shaft 2 may rotate freely, wheel 31 remaining at standstill. The Jacquard B may thus be normally driven by the loom at the proper speed and in exact correspondence with the operative cycle of the loom.

When an unweaving operation is to be effected, the operator stops the loom in the usual manner and through an appropriate switch, not shown, he energizes electromagnet 19 which through link 20 and arm 20a rocks lever 17, the latter shifting the slidable sleeve 10 towards the left in FIG. 5 and disengaging therefore teeth 10 and 24 from each other (FIG. 5). But somewhat before this disengagement is completed and while sleeves 10 and 21 are still connected angularly with each other, microswitch 26 is actuated by flange 12 and clutch 27 is energized. Gear wheel 31 is thus angularly connected with outlet shaft 2 and since pinion 34 is locked owing to the irreversible character of gearing 33, shaft 2 is already firmly retained against any tendency to rotate in any direction before it is disconnected from inlet shaft 1 by disengagement of teeth 14 and 24.

The Jacquard may now be driven at reduced speed in any direction by motor 32 independently of the loom which remains at standstill. The operator may thus run this Jacquard backwards (assuming of course that it is suitably arranged for reverse operation, as this is generally the case) and remove the successive wefts back to the defective one.

When the unweaving operation is completed, the operator disenergizes the electromagnet 19 and the parts automatically return to their initial position, teeth 14 and 24 being again in interengagement while wheel 31 is disconnected with respect to outlet shaft 2, since microswitch 26 has returned to its open position. Since sleeves 10 and 21 have only one tooth, the proper angular relation of shafts 1 and 2 is automatically obtained. All the operator might have to do is to rotate shaft 2. forwards or backwards through a small angle by means of motor 32 in order that tooth 24 may come in front of the recessed or untoothed portion of the adjacent end of sleeve 10.

Owing to the fact that the electromagnet clutch 27 is controlled by the microswitch 26, the outlet shaft 2 cannot be disconnected from the gear wheel 31 and from the irreversible speed-reducing gearing 33 before the teeth 14 and 24 of sleeves 10 and 21 are at least partially engaged, which would not be the case if the said clutch were uirler control of a switch actuated by the operator himse It i finally to be observed that when shafts 1 and 2 are disconnected with respect to each other, the loom may be operated with the Jacquard at standstill.

I claim:

1. A Jacquard driving mechanism for a loom, comprising an inlet shaft adapted to be connected with the loom to be driven by same; an outlet shaft adapted to be connected with the Jacquard to drive the latter; first clutch means interposed between said inlet shaft and said outlet shaft, said first clutch means being effective to cause said inlet shaft to positively rotate said outlet shaft, and said first clutch means being so arranged as to then maintain a pre-determined angular relation between said inlet shaft and said outlet shaft; driving means to rotate said outlet shaft at a slow speed in one and the other direction, independently of said inlet shaft, said driving means including an irreversible speed reducing gearing; second clutch means interposed between said driving means and said outlet shaft, said second clutch means, when ineffective, permitting said outlet shaft to rotate freely independently of said driving means; and means to only render said second clutch means ineffective when said first clutch means are fully effective, and to render said second clutch means effective shortly before said first clutch means are ineffective.

2. In a driving mechanism as claimed in claim 1, said second clutch means being in the form of an electromagnetic clutch and said mechanism including electric contacts actuated by said first clutch means to control said electromagnetic clutch.

3. A Jacquard driving mechanism for a loom, comprising an inlet shaft adapted to be connected with the loom to be driven by same; an outlet shaft adapted to be connected with the Jacquard to drive the latter; first clutch means interposed between said inlet shaft and said outlet shaft, said first clutch means being effective to cause said inlet shaft to positively rotate said outlet shaft, and said first clutch means embodying two rotatable members substantially disposed along the same axis, each having a single lateral tooth extending through substantially and directed towards the single tooth of the other member, and one at least of said rotatable members being axially reciprocatable to effect interengagement and disengagement of said teeth; a fixed electric contact switch disposed in the vicinity of said axially reciprocatable member of said first clutch means; a driving unit to rotate said outlet shaft at a slow speed in one or the other direction, said unit including a motor and an irreversible speed-reducing gearing; a second clutch means interposed between said driving unit and said outlet shaft, said second clutch means, when ineffective, permitting said outlet shaft to rotate freely independently of said driving member, said second clutch means being electrically controlled by said contact switch to be ineffective when the single tooth of said reciprocatable member of said first clutch means is fully engaged with the single tooth of the other tive shortly before said teeth are fully disengaged and to only become again ineffective when said teeth are at least in part engaged with each other.

References Cited UNITED STATES PATENTS 2,780,114 2/1957 Breuer et a1. 74661 member thereof, to become effec- 5 3,095,015 6/1963 Cuiengnet 3,237,648 3/1966 Grisay FOREIGN PATENTS 969,951 12/1950 France. 1,157,443 2/ 1957 Germany.

386,174 1/1933 Great Britain. 444,740 6/ 1949 Italy. 177,540 8/1935 Switzerland.

10 ROBERT A. OLEARY, Primary Examiner.

I. R. BENEFIEL, Assistant Examiner.

Examiners. 

1. A JACQUARD DRIVING MECHANISM FOR A LOOM, COMPRISING AN INLET SHAFT ADAPTED TO BE CONNECTED WITH THE LOOM TO BE DRIVEN BY SAME; AN OUTLET SHAFT ADAPTED TO BE CONNECTED WITH THE JACQUARD TO DRIVE THE LATTER; FIRST CLUTCH MEANS INTERPOSED BETWEEN SAID INLET SHAFT AND SAID OUTLET SHAFT, SAID FIRST CLUTCH MEANS BEING EFFECTIVE TO CAUSE AND INLET SHAFT TO POSITIVELY ROTATE SAID OUTLET SHAFT, AND SAID FIRST CLUTCH MEANS BEING SO ARRANGED AS TO THEN MAINTAIN A PRE-DETERMINED ANGULAR RELATION BETWEEN SAID INLET SHAFT AND SAID OUTLET SHAFT; DRIVING MEANS TO ROTATE SAID OUTLET SHAFT AT A SLOW SPEED IN ONE AND THE OHTER DIRECTION, INDEPENDENTLY OF SAID INLET SHAFT, SAID DRIVING MEANS INCLUDING AN IRREVERSIBLE SPEED REDUCING GEARING; SECOND CLUTCH MEANS INTERPOSED BETWEEN SAID DRIVING MEANS AND SAID OUTLET SHAFT, SAID SECOND CLUTCH MEANS, WHEN INEFFECTIVE, PERMITTING SAID OUTLET SHAFT TO ROTATE FREELY INDEPENDENTLY OF SAID DRIVING MEANS; AND MEANS TO ONLY RENDER SAID SECOND CLUTCH MEANS INEFFECTIVE WHEN SAID FIRST CLUTCH MEANS ARE FULLY EFFECTIVE, AND TO RENDER SAID SECOND CLUTCH MEANS EFFECTIVE SHORTLY BEFORE SAID FIRST CLUTCH MEANS ARE INEFFECTIVE. 